Characterization of Microwave-Assisted Extracts of Citrus sinensis Exocarp and Mesocarp Peels for their Pharmaceutical Excipient Potentia


  • Modupe O. Ologunagba Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.
  • Amos C. Anyaegbu Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.
  • Chukwuemeka P. Azubuike Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.
  • Boladale O. Silva Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.


microwave-assisted extraction, excipient potential, microbial and toxicological safety, characterizations, Citrus sinensis peel extracts


Natural plants wastes are increasingly explored for their excipient potentials in alignment with the present global focus on economic and sustainable waste utilization. This study characterized microwave-assisted extracts of Citrus sinensis exocarp (Cs- Exop) and mesocarp peels (Cs-Mesop) using standard protocols. The two extracts had distinctive organoleptic properties. Their respective mean particle sizes being (120.80 ± 0.12 and 99.70 ± 0.0.15 μm); pH (5.52 and 6.41); swelling index (2.08 ± 0.02 and 3.01 ± 0.07); water binding capacity (1.77 ± 0.03 and 3.32 ± 0.02 %); viscosity (12.6 ± 0.4 and 19.5 ± 0.4 mPa.s); moisture content (13.30 ± 0.17 and 18.78 ± 0.14 %); Hausner’s ratio (1.35 ± 0.01 and 1.30 ± 0.01); compressibility index (22.2 ±0.01 and 20.3 ± 0.01) among others. The microbial evaluation revealed the absence of objectionable microorganisms; the total aerobic microbial counts were 8.00 x 102 and 19.50 x 102; yeast and mould counts were 2.00 x 102 and 6.00 x 102 respectively which were in conformity to the specifications of United States Pharmacopoeia. They both had safety profiles with the lethal dose (LD50 ) values ≥ 5000 mg/kg. No occurrence of morbidity, mortality,
abnormalities on the hematological and histopathology profiles at all the administered doses in the experimental animals. No statistical significance occurred between the Control and the CS-peels treated groups. Citrus sinensis peel extracts have desirable pharmaceutical excipient attributes. Cs- Exop peel extract can be employed as a permeation enhancer,
emulgent while Cs -Mesop can serve as a potential binder and disintegrant.


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How to Cite

Ologunagba, M. O., Anyaegbu, A. C., Azubuike, C. P., & Silva, B. O. (2023). Characterization of Microwave-Assisted Extracts of Citrus sinensis Exocarp and Mesocarp Peels for their Pharmaceutical Excipient Potentia: Tropical Journal of Phytochemistry and Pharmaceutical Sciences, 2(1), 38–47. Retrieved from